This photo taken on Dec. 7, 2009 shows the gruidaes fly in the Qilihai wetland in Qinhuangdao, north China's Hebei Province. Large flocks of migratory birds from the north to south have arrived in Qinhuangdao as local environment works on protecting the wetland.

This photo taken on Dec. 7, 2009 shows the gruidaes fly in the Qilihai wetland in Qinhuangdao, north China's Hebei Province. Large flocks of migratory birds from the north to south have arrived in Qinhuangdao as local environment works on protecting the wetland.

Source: Xinhua